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TROUBLESHOOTING CONTENTS
Troubleshooting of electronic control systems for which the scan tool can be used follows the basic outline described below. Even in systems for which the scan tool cannot be used, part of these systems still follow this outline.
 
 
1. STANDARD FLOW OF DIAGNOSTIC TROUBLESHOOTING
Troubleshooting strategy is shown in each group.
 
 
2. SYSTEM OPERATION AND SYMPTOM VERIFICATION TESTS
If verification of the symptom(s) is difficult, procedures for checking operation and verifying symptoms are shown.
 
 
3. DIAGNOSTIC FUNCTION
The following trouble code diagnosis are shown.
  • How to read diagnostic trouble codes
  • How to erase diagnostic trouble codes
  • Input inspection service points
 
 
4. DIAGNOSTIC TROUBLE CODE CHART
If the scan tool displays a diagnostic trouble code, find the applicable inspection procedure according to this chart.
 
 
5. SYMPTOM CHART
If there are symptoms, even though the scan tools show that no DTCs are stored, inspection procedures for each symptom will be found by using this chart.
 
 
6. DIAGNOSTIC TROUBLE CODE PROCEDURES
Indicates the inspection procedures corresponding to each diagnostic trouble code. (Refer to ).
 
 
7. SYMPTOM PROCEDURES
Indicates the inspection procedures corresponding to each symptom listed in the Symptom Chart. (Refer to ).
 
 
8. SERVICE DATA REFERENCE TABLE
Inspection items and normal judgment values have been provided in this chart as reference information.
 
 
9. CHECK AT ECU TERMINALS
Terminal numbers for the ECU connectors, inspection items, and standard values have been provided in this chart as reference information.
 
 
TERMINAL VOLTAGE CHECKS
1. Connect a needle-nosed wire probe to a voltmeter probe.
cautionShort-circuiting the positive (+) probe between a connector terminal and ground could damage the vehicle wiring, the sensor, the ECU, or all three. Use care to prevent this!
2. Insert the needle-nosed wire probe into each of the ECU connector terminals from the wire side, and measure the voltage while referring to the check chart.
noteMeasure voltage with the ECU connectors connected.
You may find it convenient to pull out the ECU to make it easier to reach the connector terminals.
Checks don't have to be carried out in the order given in the chart.
3. If voltage readings differ from normal condition values, check related sensors, actuators, and wiring. Replace or repair as needed.
4. After repair or replacement, recheck with the voltmeter to confirm that the repair has corrected the problem.
 
 
TERMINAL RESISTANCE AND CONTINUITY CHECKS
1. Turn the ignition switch to the "LOCK" (OFF) position.
2. Disconnect the ECU connector.
cautionIf resistance and continuity checks are performed on the wrong terminals, damage to the vehicle wiring, sensors, ECU, and/or ohmmeter may occur. Use care to prevent this!
3. Measure the resistance and check for continuity between the terminals of the ECU harness-side connector while referring to the check chart.
noteChecks don't have to be carried out in the order given in the chart.
4. If the ohmmeter shows any deviation from the Normal Condition value, check the corresponding sensor, actuator and related electrical wiring, then repair or replace.
5. After repair or replacement, recheck with the ohmmeter to confirm that the repair has corrected the problem.
 
 
10. INSPECTION PROCEDURES USING AN OSCILLOSCOPE
When there are inspection procedures using an oscilloscope, these are listed.